Internal combustion engines operate by converting chemical energy stored within combustible fuels to mechanical energy. When an internal combustion engine is employed in a vehicle, the mechanical energy is typically converted to torque for impelling rotational motion in the wheels of the vehicle. Vehicles often include a fuel system configured to provide desired amounts of fuel to combustion chambers of the engine at precise times. In one example, such fuel systems include a fuel supply tank for storing fuel, a fuel line coupling the fuel tank to the engine, a fuel pump situated on said fuel line for delivering fuel from the fuel tank to the engine at a desired pressure, and a fuel pipe for supplying additional fuel to the fuel tank. A fuel pipe includes a first end connected to a fuel tank port of the fuel tank and a second end connected to a vehicle fueling port that is typically located at an exterior side wall of the vehicle. Because of the volatile nature of fuel, breaches at any location in the fuel system may allow fuel vapor to escape to the atmosphere.
Even a well-sealed fuel system may experience fuel leakage or spillage in the event of a high-impact vehicle collision. Attempts to address fuel system breaches due to vehicle collisions include blocking fluidic communication between the fuel tank and the engine via a valve in response to extreme impacts. One example approach is shown by Lassiter in U.S. Pat. No. 6,354,261. Therein, a solenoid valve is held in an energized position during engine operation via an impact-sensitive switch. Upon high impacts, the impact-sensitive switch is dislocated from a first position to a second position, and in response the solenoid valve moves from an energized position to a de-energized position. In the de-energized position, the solenoid valve prevents the passage of fuel between the fuel tank and the fuel pump. In this way, fuel is not supplied to the fuel pump if a high impact may have created a fuel system breach near the engine, thereby reducing the chance fuel escaping from the vehicle fuel system.
However, the inventors herein have recognized potential issues with such systems. As one example, blocking fluid communication between the fuel tank and the engine may not reduce leakage via other ports on the fuel tank. For example, if the fuel pipe coupling the vehicle fueling port to the fuel tank is ruptured, for example via a side-on collision, fuel may leak from the fuel tank through the rupture in the fuel pipe (e.g., as fuel vapor).
In one example, the issues described above may be addressed by a system for a vehicle, comprising a side fueling port fluidly and physically coupled to a fuel tank via a fuel pipe including a detachable nozzle, and a controller with computer-readable instructions stored thereon for disengaging the nozzle from the fuel tank in response to receiving a signal from an impact sensor indicating a vehicle side impact. In this way, fuel leakage through a fuel pipe that has been degraded via a collision may be reduced.
As one example, a fuel pipe nozzle of a fuel pipe coupling a vehicle fueling (e.g., re-filling) port to a fuel tank of an engine fuel system may be engaged in a self-sealing fuel tank port of the fuel tank. An actuator may be configured to effect translational motion of the nozzle along the interfacial axis of the self-sealing fuel tank port and the fuel pipe nozzle. In response to a detected impact event, a vehicle controller may control the actuator to translate the nozzle from an engaged position to a disengaged position. The engaged position may include a physical and fluidic coupling between the fuel tank port and the vehicle fueling port, and the disengaged position may include neither a physical coupling nor a fluidic coupling between the fuel tank port and the vehicle fueling port. Moving the side fueling port from an engaged position to a spaced-apart disengaged position may include retracting the nozzle from the fuel tank coupling by a small predetermined distance, thereby removing the physical and fluidic couplings between the fuel tank and fuel pipe, and allowing the fuel tank port to move to a closed position via a self-sealing mechanism. In this way, the fuel tank may be quickly sealed from the side fueling port in the event of a high impact collision.
It should be understood that the summary above is provided to introduce in simplified form a selection of concepts that are further described in the detailed description. It is not meant to identify key or essential features of the claimed subject matter, the scope of which is defined uniquely by the claims that follow the detailed description. Furthermore, the claimed subject matter is not limited to implementations that solve any disadvantages noted above or in any part of this disclosure.